CVE-2025-51398
📋 TL;DR
A stored cross-site scripting (XSS) vulnerability in Live Helper Chat v4.60 allows attackers to inject malicious scripts into the Facebook registration page's Name parameter. When other users view the compromised registration data, their browsers execute the attacker's arbitrary web scripts or HTML. This affects all deployments using the vulnerable version of Live Helper Chat with Facebook registration enabled.
💻 Affected Systems
- Live Helper Chat
📦 What is this software?
Live Helper Chat by Livehelperchat
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal session cookies, perform account takeovers, redirect users to malicious sites, or perform actions on behalf of authenticated users, potentially leading to complete system compromise.
Likely Case
Attackers steal user session cookies to hijack accounts, deface chat interfaces, or redirect users to phishing pages.
If Mitigated
With proper input validation and output encoding, malicious scripts are rendered harmless as plain text rather than executable code.
🎯 Exploit Status
Proof of concept available in GitHub repository. Exploitation requires access to the Facebook registration page but no authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in commit 2056503ad96e04467ec9af8d827109b9b9b46223
Vendor Advisory: https://github.com/LiveHelperChat/livehelperchat/pull/2228/commits/2056503ad96e04467ec9af8d827109b9b9b46223
Restart Required: No
Instructions:
1. Update to the latest version of Live Helper Chat. 2. Apply the specific commit that fixes the XSS vulnerability. 3. Verify the fix by testing the Facebook registration page with XSS payloads.
🔧 Temporary Workarounds
Disable Facebook Registration
allTemporarily disable the Facebook registration feature to prevent exploitation.
Edit configuration to disable Facebook registration
Implement Input Validation
allAdd server-side input validation to sanitize the Name parameter.
Implement input sanitization for the Name field in registration forms
🧯 If You Can't Patch
- Implement a web application firewall (WAF) with XSS protection rules
- Enable Content Security Policy (CSP) headers to restrict script execution
🔍 How to Verify
Check if Vulnerable:
Test the Facebook registration page by submitting a payload like <script>alert('XSS')</script> in the Name field and check if it executes when viewed.Check Version:
Check the Live Helper Chat version in the admin panel or configuration files.Verify Fix Applied:
After patching, repeat the XSS test to ensure the payload is properly sanitized and does not execute.📡 Detection & Monitoring
Log Indicators:
- Unusual characters or script tags in registration logs
- Multiple failed registration attempts with special characters
Network Indicators:
- HTTP requests with script tags in POST data to registration endpoints
SIEM Query:
source="web_logs" AND (uri="/facebook/registration" OR uri LIKE "%/register%") AND (data LIKE "%<script>%" OR data LIKE "%javascript:%")